Merge pull request #644 from NativeScript/nnikolov/BindingIssueWithNullSourceProperty

Fixed issue with binding when there is no sourceProperty set.

apps/tests/ui/bindable-tests.ts

@@ -888,3 +888,21 @@ export function test_NestedPropertiesBindingTwoTargetsAndReplacingSomeNestedObje
 
     TKUnit.assertEqual(target2.get("targetProp"), secondExpectedFirstName);
 }
+
+export function test_NullSourcePropertyShouldNotCrash() {
+	var expectedValue = "Expected Value";
+	var target = new bindable.Bindable();
+	var convFunc = function (value) {
+		return value + "Converted";
+	}
+	var model = new observable.Observable();
+	model.set("field", expectedValue);
+	model.set("convFunc", convFunc);
+	target.bind({
+		sourceProperty: null,
+		targetProperty: "targetProp",
+		expression: "convFunc(field)"
+	}, model);
+
+	TKUnit.assertEqual(target.get("targetProp"), convFunc(expectedValue)); 
+}

ui/core/bindable.ts

@@ -187,9 +187,14 @@ export class Binding {
         return this.sourcePropertiesArray;
     }
 
-    private static getProperties(property: string) {
+    private static getProperties(property: string): Array<string> {
+		if (property) {
 			return property.split(".");
 		}
+		else {
+			return [];
+		}
+    }
 
     private resolveObjectsAndProperties(source: Object, propsArray: Array<string>) {
         var result = [];